FIG. 1 is a flow chart depicting a conventional method 10 for fabricating a conventional perpendicular magnetic recording (PMR) transducer. For simplicity, some steps are omitted. The conventional method 10 commences after the high moment layer(s) for the PMR pole are deposited, for example by plating. At least a hard mask is provided, via step 12. Step 12 may also include depositing other conventional layers, such as a chemical mechanical planarization (CMP) stop layer. The hard mask and other layers may be blanket deposited, then patterned using conventional photolithography. The pole layer(s) are then trimmed, via step 14. Step 14 is used to form the conventional PMR pole. The top, or trailing edge, of the conventional PMR pole is thus wider than the bottom of the conventional PMR pole.
Side gap material(s) may then be deposited, via step 16. Step 16 typically includes depositing a nonmagnetic layer, such as aluminum oxide. Side shield material(s) may then be deposited, via step 18. Step 18 may be used if side shields are desired for the conventional PMR transducer. A CMP is then performed, via step 20. The stop layer that might be provided in step 12 might be used to terminate the CMP.
Bevel(s) may also be provided in the conventional PMR pole, via step 22. If a top bevel is to be provided, step 22 may include removing a top portion of the ferromagnetic pole materials in the region that the air-bearing surface (ABS) is to be formed. As a result, the top surface of the conventional PMR pole near the ABS is lower than the yoke portion of the PMR pole. If step 22 is to be used to form a bottom bevel, the step 22 is typically performed earlier in the method 10, for example prior to step 12. In such a case, step 22 may be used to ensure that the topology of the layer(s) on which the conventional PMR pole is formed is higher in proximity to the ABS. Step 22 may include masking a portion of the underlayer(s) and refilling the layer(s) near the ABS. In such a case, this portion of step 22 is performed before steps 12 and 14. As a result, a bottom bevel may be formed.
The write gap may then be provided, via step 24. Step 24 may include depositing a thin nonmagnetic layer that covers at least the top of the pole near the ABS. A portion of the write gap may optionally be removed, via step 26. Part of the write gap may be removed if the side shields are desired to be electrically connected to a top shield, forming a wrap around shield. Step 26 would then typically include providing a mask that covers the pole and side gaps and removing the exposed portion of the write gap. If the top shield is desired to float, or be electrically unconnected to the side shields, then step 26 may be omitted. The conventional top shield may then be provided, via step 28. Fabrication of the conventional PMR transducer may then be completed.
FIG. 2 depicts a conventional PMR transducer 50 formed using the method 10. The conventional PMR transducer 50 includes a pole 54 formed on one or more conventional underlayers 52. Also shown are conventional side gaps 56, conventional side shields 58, conventional write gap 60, and conventional top shield 62. In the conventional PMR transducer 50, the conventional side shields 58 are electrically connected to the conventional top shield 62, to form a conventional wrap around shield.
Although the conventional method 10 may provide the conventional PMR transducer 50, there may be drawbacks. Misalignment may occur in, for example, step 26. More specifically, the mask used to cover the pole 54 during formation of the conventional write gap 60 may not be centered on the pole 54. As a result, there may be more stray edge fields during use of the conventional PMR transducer. If portions of the write gap 58 are not removed, the conventional top shield 60 may float. Such a conventional PMR transducer may also have higher edge stray fields. Consequently, the conventional PMR transducer 50 may be subject to erasure issues, for example erasure of side tracks. Performance of the conventional PMR transducer 50 may thus be compromised.
Accordingly, what is needed is an improved method for fabricating a PMR transducer.